If X, Then Y
by Luna Darkside
Summary: Shinichi is a firm believer in logic - for every effect, there's a cause. But, um, it's kind of difficult to explain how he ended up in bed with Kaito. Naked. /ShinKai, oneshot, complete/


_Not sure how this happened. I had the original idea, but I didn't know where I was going with it. So this is pretty random._

_Anyway, usual warnings apply. ShinKai (aka shounen ai), possible grammar mistakes/typos, etc._

_Well, hope you enjoy! - Luna_

**If X, Then Y**

It went without saying that Shinichi was a fan of logic. As a detective, he automatically saw cause and effect everywhere. It was a bit of an occupational hazard.

The sky was blue because of Rayleigh scattering. People committed murder for love, money, or revenge. Salt melted ice because it lowered the freezing point of water. He was currently naked next to Kaito because –

…because?

Wait, _naked_ _next_ _to_ _Kaito_?!

Shinichi nearly fell off the bed, staring at the face pressed into his shoulder in shock. That… yep, that was definitely Kaito. The magician's eyes were still shut, his cheek buried in Shinichi's collarbone. His hair was a dark brown tangle against the white pillows, and his breath was warm against Shinichi's skin. Also, Shinichi was about ninety-nine percent sure that Kaito's (bare) leg was against his.

This was, um, very awkward.

For God's sake, he'd only known Kaito (as Kaito) for two months! They'd only met _recently_!

(Although, technically, he and Kid had been acquainted for much, much longer. Something like four years…?)

On the verge of breaking out into a sweat, Shinichi lay there, statue-still. This was Kaito's bed, right? What _happened _last night? There had to be some kind of logical conclusion for this. There _had _to be. Other than that they had, er…

His head took this opportunity to begin throbbing violently, calmly informing Shinichi that he had a killer hangover. Just what he needed.

Kaito made a soft snuffling sound, nosing deeper into Shinichi's shoulder. Shinichi stiffened instantly, brain going at light speed. _What-was-he-supposed-to-do-oh-God-his-leg-moved-damn-it-all-run_ –!

Still doing mental gymnastics in rapid succession, Shinichi struggled out of Kaito's grip, trying to be as quiet as possible as he stood up. Kaito mewled softly and burrowed into the pillow, still asleep. Shinichi exhaled slowly. Good. That was good.

Flinching, Shinichi glanced around the room. His clothes were strewn in a haphazard pile off in one corner, and he swallowed dryly. Careful to be as silent as possible, he crossed the room and wriggled into his clothes.

On the bed, Kaito stirred. Shinichi froze. When the magician just hugged the pillow tighter to himself, Shinichi let out a breath and nearly sprinted from the room.

Shinichi was still frantically trying to think when he paused by the kitchen. Well, even if he had absolutely no idea what happened, he didn't have to be a jerk, did he? Running like this was pretty rude, after all.

His head pulsed with pain, and he cringed.

No, really, Shinichi should probably go. He – just… what would Kaito think if he knew he'd slept with Shinichi? He'd probably hate Shinichi forever, and the detective really didn't know if he could handle that. It would be better if Kaito had no idea what had happened. Yes.

But that would be so _cold_…

Gripping his bangs, Shinichi nearly groaned out loud. "I'm an idiot," he grumbled to himself as he stalked into the kitchen.

* * *

The first thing Kaito was aware of was that his head was pounding and his mouth felt sandy. Not exactly comfortable.

The second thing he was aware of was that the bed was empty. A frown creased his eyebrows, and Kaito forced himself to open his eyes. Weird. He could've sworn that there had been something warm in there…

And the third thing Kaito was aware of was that there was a glass of water on the bedside table along with two painkillers.

Surprised, Kaito dragged himself up into a sitting position, yawning so widely his eyes teared up and his head shuddered in pain. There was no note beside the water and the painkillers, and Kaito was absolutely positive that he hadn't put them there before. What was going on?

Well, whoever it was, Kaito was thankful. He swallowed the painkillers and downed the glass of water, wiping his mouth with the back of his hand. Ugh, how much had he drunken last night? Three gallons of whiskey?

Standing unsteadily (oh, was this what it felt like to be on a boat), Kaito located his clothes and yanked them on before he staggered out of the room. The house was empty save for him, it seemed. Odd. Kaito scowled down the shadowy, empty hallway. He hadn't been alone, right? Had the other person left?

Kaito headed for the kitchen, intent on getting himself some more water. His throat still felt as if he'd spent the weekend in the Sahara Desert. He pulled open the refrigerator, staring listlessly into its depths.

It took him a second to notice the cup of still-steaming ginger tea sitting on the counter beside him.

Kaito jerked, letting go of the refrigerator door. It slammed shut ominously, but Kaito ignored it in favor of gawking at his favorite mug. Okay, so there definitely _had _been someone here recently.

But who the hell had it been?

* * *

"Hattori?" Shinichi asked, harried, as he strode briskly down the sidewalk. "Can you come get me?"

On the other end, the Osakan, who'd been staying at the Kudou residence for the past three days, sighed loudly. "Do you make all your guests come get you?"

"Not usually. But I don't have money for the subway for some reason, and I don't know where to go," explained Shinichi, looking up at the sky. It was a depressing shade of shale gray, and it stared gloomily back at him, as if asking _what are you looking at? _"Do you mind?"

"Of course I mind. But I'll come anyway, seeing as I'm such a great friend," Hattori answered, and Shinichi scowled, hearing the grin in his voice. "Where are you?"

"Um… Ekoda."

"…Are you going to tell me why you're in Ekoda at eight thirty five in the morning?"

Stopping by a bus stop, Shinichi wrestled a section of his hair out of his face. His head grumbled, and he groaned mentally. He'd taken some painkillers back at Kaito's place, but apparently pain was pretty resilient. "Um, no."

Hattori's voice took on a distinctively suspicious note. "Does it have anything to do with attending that Kid heist?"

"Would you believe me if I said no?"

"Probably not, no."

"Then why do you even bother asking?" Shinichi sighed hard. "So can you come get me or not?"

"Su~re, Kudou." Shinichi was relieved. Unfortunately, it was short-lived, because Hattori continued, "As long as you tell me about who you met. Is she pretty?"

"Er…" Shinichi momentarily wondered if Kaito could be considered pretty. He was certainly good looking, but _pretty_…? "Sort of."

"Sort of? How can someone be 'sort of' pretty?"

"It's possible."

"Not for you." Hattori's voice took on a sardonic note. "You're a hot, young, single detective. You've got your pick of the ladies."

Shinichi blanched. "Never call me hot again."

"But seriously."

"Not seriously." This was starting to get exhausting. Shinichi pressed his free hand to the back of his neck. A breeze chilled his ears. He felt… tired. And almost guilty for leaving Kaito behind. It was completely irrational for him to feel as if he'd abandoned Kaito, but he still felt it.

In a moment of weakness, Shinichi asked, "Hey, Hattori… what would you do if you woke up next to someone you know well with a hangover?"

"Um… why are you asking that all of a sudden?"

"Just answer the question."

"You're serious." A breath, then, "Well, I don't know. Is either of us wearing clothes?"

"No."

"Then I'd assume that we, uh…" A cough. "You know. I'm not going into details. And that's really awkward."

"Thank you for your help." So much help, his best friend was. Shinichi was about to ask him to never mind and come get him when Hattori continued.

"I'd probably stay."

"What?"

"I'd stay until they woke up. Because obviously if I slept with someone I knew well, I was probably in love with them without knowing it. Alcohol doesn't _create _feelings, y'know. It makes you act on ones you didn't know you had."

_Makes you act on ones you didn't know you had?_

Shinichi stood there in the biting cold, a combination of equal parts shocked and confused and _what does this even mean? _Clearly Hattori was right – that was only logical; alcohol didn't have _that _much effect – but applied to his situation, didn't it mean he was…? With Kaito…?

What _did_ he feel for the magician? He admired him – it took a lot to plan heists – and he certainly found him _physically _attractive. And he loved his company – almost no one else could match wits with Shinichi as easily. And… oh God he really was in love with Kaito.

Shinichi cleared his throat. "That was deep, Hattori."

"I know." His best friend paused for a beat. "Look, Kudou, do you still want me to come get you?" A slight smile. "Or have I changed your mind?"

Shinichi made a split-second decision. "You know what, you actually have. For once." He turned to glance back in the direction of the familiar little house a block away. "I have something to do over here."

* * *

Kaito was about three-fourths surprised and one-fourth not when he opened the front door to find Shinichi standing there.

Realization flooded him, and Kaito started, pointing accusingly at the detective. "You! It was you!" That was right! Last night, he and Shinichi had met up after his heist, and they'd –

Shinichi rubbed the back of his head. "Uh, yes. Sorry… about leaving."

"No, I can understand." Kaito baulked at the memories – _competitive smile, eyes darkened, bare skin _– and leaned against the doorframe. "That was some night we had. Pretty intense."

"Oh." Shinichi was staring at him with a look of abject horror. "I… I just wanted to say that I'll take responsibility."

Bewildered, Kaito raised an eyebrow. "What? What do you mean by that?"

"Well, because –" Shinichi broke off. He took a step forward and grasped Kaito firmly by the shoulders, forcing them to face each other. Kaito jumped a little, face warming at the contact. Did Shinichi _know _how he made him feel just by touching him –

"I'm sorry that I slept with you while drunk and ran this morning. I was just scared and confused and… there's really no excuse. But I just want you to know that I'm in love with you. Probably," the detective stated determinedly, blindingly azure eyes locked on Kaito's.

Kaito blinked once. Twice.

"What?"

With a sigh, Shinichi dropped his hands from Kaito's shoulders. "I'm _pretty _sure I'm in love with you, at least. I mean… I didn't know that I was in love with you _before_, but there was definitely some kind of attraction for me to want to sleep with you while I was drunk. I know now." He took a deep breath. "I love you."

Speechless, Kaito just stared. This could not be happening. He must be hallucinating. Life was never this… perfect. Except – "Don't get me wrong. I love you too, and this is amazing, but…"

"You do?" Shinichi's face lit up.

"…we didn't sleep together."

"…Explain."

"You really don't remember?" Kaito wasn't sure if he should be laughing or crying. Maybe both. "You came over after the heist, and we starting having congratulatory drinks. But then we got pretty drunk, and one of us had the amazing idea to play strip poker." He slanted his head at Shinichi. "And then we got tired, so we went to bed. Without putting our clothes back on, that is. We didn't sleep together."

The expression on Shinichi's face could probably be described as a mixture of shock and dismay. Kaito sighed, feeling his heart drop back down somewhere near the center of the earth.

"Don't worry about it, then. See you around, Kudou," he muttered, moving to close the door.

"Wait." Shinichi lurched forward and grabbed Kaito, spinning him around. Kaito was about to protest when his lips were suddenly against Shinichi's and oh whoa this was about twelve kinds of perfect.

Kaito pulled back a minute later, head spinning. He felt very… warm. "Kudou –"

"You know," Shinichi said calmly, "I think we can fix the not-sleeping together thing. What about you?"

"I –" Kaito faltered. Shinichi's eyes had definitely darkened, but he could see there was something there – something like _I'm not lying to you _and _I love you _and _I'm sorry _all in one.

He allowed himself to smile. "I agree."

Shinichi grinned back. He was going to have to thank Hattori later, but logic was _definitely_ his new favorite thing, he decided as he followed Kaito back into the house.

That, or Kaito.

* * *

**I'm such a sap. It's sad.**

**Whelp, hope you liked this, um, epic fail even a little. Drop me a review, k?**

**See you later, my lovelies! - Luna**


End file.
